Pubmed du 03/09/14

Pubmed du jour

2014-09-03 12:03:50

1. {{Expression of concern: measles-mumps-rubella vaccination timing and autism among young African American boys: a reanalysis of CDC data}}. {Translational neurodegeneration}. 2014;3:18.

The Publisher of this article [1] has serious concerns about the validity of its conclusions because of possible undeclared competing interests of the author and peer reviewers. The matter is undergoing investigation. In the meantime, readers are advised to treat the reported conclusions of this study with caution. Further action will be taken, if appropriate, once our investigation is complete.

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2. Balogh RS, Lake JK, Lin E, Wilton A, Lunsky Y. {{Disparities in diabetes prevalence and preventable hospitalizations in people with intellectual and developmental disability: a population-based study}}. {Diabetic medicine : a journal of the British Diabetic Association}. 2014 Sep 3.

AIMS: To describe and compare population-level aspects of diabetes and diabetes primary care among people with and without intellectual and developmental disabilities. METHODS: Administrative health data accessed from the Institute for Clinical Evaluative Sciences was used to identify a cohort of Ontarians with and without intellectual and developmental disabilities between the ages of 30 and 69 years (n=28 567). These people were compared with a random sample of people without intellectual and developmental disabilities (n=2 261 919) according to diabetes prevalence, incidence, age, sex, rurality, neighbourhood income and morbidity. To measure diabetes primary care, we also studied hospitalizations for diabetes-related ambulatory care-sensitive conditions. RESULTS: Adults with intellectual and developmental disabilities had a consistently higher prevalence and incidence of diabetes than those without intellectual and developmental disabilities. Disparities in prevalence between those with and without intellectual and developmental disabilities were most notable among women, younger adults and those residing in rural or high income neighbourhoods. In terms of hospitalizations for diabetes-related ambulatory care-sensitive conditions, people with intellectual and developmental disabilities were 2.6 times more likely to be hospitalized. CONCLUSIONS: Adults with intellectual and developmental disabilities are at high risk of developing and being hospitalized for diabetes. The findings of the present study have a number of important implications related to the early detection, prevention and proper management of diabetes among adults with intellectual and developmental disabilities. This article is protected by copyright. All rights reserved.

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3. Bey AL, Jiang YH. {{Overview of mouse models of autism spectrum disorders}}. {Current protocols in pharmacology / editorial board, SJ Enna (editor-in-chief) [et al]}. 2014;66:5 66 1-5 26.

This overview describes many well characterized mouse models of autism spectrum disorders (ASDs). Mouse models considered here were selected because they are examples of genetically engineered models where human genetic evidence supports a causative relationship between the targeted mutation and the behavioral phenotype. As the ASD diagnosis is based primarily on behavioral evaluations in humans in the domains of social interaction, communication, and restricted interests, the murine phenotypes analogous to human autistic behaviors are highlighted for the different models and behaviors. Although genetically engineered mouse models with good construct and face validity are valuable for identifying and defining underlying pathophysiological mechanisms and for developing potential therapeutic interventions for the human condition, the translational value of various rodent behavioral assays remains a subject of debate. Significant challenges associated with modeling ASDs in rodents because of the clinical and molecular heterogeneity that characterize this disorder are also considered. Curr. Protoc. Pharmacol. 66:5.66.1-5.66.26. (c) 2014 by John Wiley & Sons, Inc.

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4. Bodner KE, Williams DL, Engelhardt CR, Minshew NJ. {{A Comparison of Measures for Assessing the Level and Nature of Intelligence in Verbal Children and Adults with Autism Spectrum Disorder}}. {Res Autism Spectr Disord}. 2014 Nov 1;8(11):1434-42.

Previous work has suggested that the Raven’s Progressive Matrices (RPM) are better suited for capturing the nature of intelligence for individuals with autism spectrum disorder (ASD) than the Wechsler scales. The RPM measures ‘fluid intelligence’, an area for which it has been argued that persons with ASD have a relative strength. Given that measures of intelligence are used for establishing clinical diagnoses, for making educational decisions, and for group-matching in research studies, continued examination of this contention is warranted. In the current study, verbal children with ASD performed moderately better on the RPM than on the Wechsler scales; children without ASD received higher percentile scores on the Wechsler than on the RPM. Adults with and without ASD received higher percentile scores on the Wechsler than the RPM. Results suggest that the RPM and Wechsler scales measure different aspects of cognitive abilities in verbal individuals with ASD. For the verbal children and adults with ASD in the current study, the RPM and Wechsler scales have unique contributions that must be considered in context when establishing a baseline of cognitive function. The results of this investigation highlight the importance of thoughtfully selecting appropriate measures of intelligence consistent with clinical, educational, and research purposes, especially for verbal children and adults with ASD.

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5. Bowling H, Klann E. {{Shaping Dendritic Spines in Autism Spectrum Disorder: mTORC1-Dependent Macroautophagy}}. {Neuron}. 2014 Sep 3;83(5):994-6.

In this issue of Neuron, Tang et al. (2014) explore the relationship between developmental dendritic pruning, elevated mTORC1 signaling, macroautophagy, and autism spectrum disorder. The study provides valuable new insight into mTORC1-dependent cellular dysfunction and neurodevelopmental disorders.

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6. Coben R, Ricca R. {{EEG Biofeedback for Autism Spectrum Disorder: A Commentary on Kouijzer et al. (2013)}}. {Applied psychophysiology and biofeedback}. 2014 Sep 2.

Research conducted by Kouijzer et al. (Appl Psychophysiol Biofeedback 38(1):17-28, 2013) compared the effects of skin conductance biofeedback and EEG-biofeedback on patients with autistic spectrum disorders to determine their relative efficacy. While they found a difference between treatment and control groups, there was no significant difference on many variables between the two treatment groups. From this, the increase in symptom alleviation from autistic spectrum disorder was attributed to non-specific factors surrounding the study. We now offer alternative explanations for their findings and propose different options for future studies. We hypothesize that the location and type of neurofeedback used adversely impacted the findings. We speculate that had they used a form of EEG-biofeedback that can combat deficiencies in connectivity and also trained the areas of the brain most affected by autism, there may have then been a significant difference between the effectiveness of EEG-biofeedback versus skin conductance biofeedback.

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7. Corbett BA, Newsom C, Key AP, Qualls LR, Edmiston EK. {{Examining the relationship between face processing and social interaction behavior in children with and without autism spectrum disorder}}. {Journal of neurodevelopmental disorders}. 2014;6(1):35.

BACKGROUND: Children with autism spectrum disorder (ASD) show impairment in reciprocal social communication, which includes deficits in social cognition and behavior. Since social cognition and social behavior are considered to be interdependent, it is valuable to examine social processes on multiple levels of analysis. Neuropsychological measures of face processing often reveal deficits in social cognition in ASD including the ability to identify and remember facial information. However, the extent to which neuropsychological measures are associated with or predictive of real-world social behavior is unclear. METHODS: The study investigated 66 children (ASD 34, typically developing (TD) 32) using neuropsychological measures of face processing (identity, affect, and memory). Children also participated in a peer interaction paradigm, which allowed observation and coding of natural social interaction behaviors during play with peers (e.g., Self-Play, Cooperative Play, Verbal Bout). ANCOVA, regression, and correlation models analyzed between-group differences, the ability of neuropsychological measures to predict social behavior, and the strength of the associations. RESULTS: Between-group differences were shown on Memory for Faces Delayed and the peer interaction variables Self-Play and Verbal Bout. Regression models indicated that Memory for Faces Delayed predicted the amount of Self-Play, Equipment use alone, and Cooperative Play with peers on the playground. Autism symptomology only predicted verbal exchange with peers. CONCLUSIONS: Face memory strongly predicts relevant social engagement patterns in both children with and without ASD. Impairment in facial memory is associated with reduced ‘real-world’ social interaction and more self-play, whereas higher performance in face memory predicts more cooperative play. Results highlight the strong connection between face memory and reciprocal social interaction, suggesting that improvement in one may benefit the other.

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8. de Diego-Otero Y, Calvo-Medina R, Quintero-Navarro C, Sanchez-Salido L, Garcia-Guirado F, Del Arco-Herrera I, Fernandez-Carvajal I, Ferrando-Lucas T, Caballero-Andaluz R, Perez-Costillas L. {{A combination of ascorbic acid and alpha-tocopherol to test the effectiveness and safety in the fragile X syndrome: study protocol for a phase II, randomized, placebo-controlled trial}}. {Trials}. 2014 Sep 3;15(1):345.

BACKGROUND: Fragile X syndrome (FXS) is an inherited neurodevelopmental condition characterised by behavioural, learning disabilities, phisical and neurological symptoms. In addition, an important degree of comorbidity with autism is also present. Considered a rare disorder affecting both genders, it first becomes apparent during childhood with displays of language delay and behavioural symptoms.Main aim: To show whether the combination of 10 mg/kg/day of ascorbic acid (vitamin C) and 10 mg/kg/day of alpha-tocopherol (vitamin E) reduces FXS symptoms among male patients ages 6 to 18 years compared to placebo treatment, as measured on the standardized rating scales at baseline, and after 12 and 24 weeks of treatment.Secondary aims: To assess the safety of the treatment. To describe behavioural and cognitive changes revealed by the Developmental Behaviour Checklist Short Form (DBC-P24) and the Wechsler Intelligence Scale for Children-Revised. To describe metabolic changes revealed by blood analysis. To measure treatment impact at home and in an academic environment. METHODS: A phase II randomized, double-blind pilot clinical trial. Scope: male children and adolescents diagnosed with FXS, in accordance with a standardized molecular biology test, who met all the inclusion criteria and none of the exclusion criteria. Instrumentation: clinical data, blood analysis, Wechsler Intelligence Scale for Children-Revised, Conners parent and teacher rating scale scores and the DBC-P24 results will be obtained at the baseline (t0). Follow up examinations will take place at 12 weeks (t1) and 24 weeks (t2) of treatment. DISCUSSION: A limited number of clinical trials have been carried out on children with FXS, but more are necessary as current treatment possibilities are insufficient and often provoke side effects. In the present study, we sought to overcome possible methodological problems by conducting a phase II pilot study in order to calculate the relevant statistical parameters and determine the safety of the proposed treatment. The results will provide evidence to improve hyperactivity control and reduce behavioural and learning problems using ascorbic acid (vitamin C) and alpha-tocopherol (vitamin E). The study protocol was approved by the Regional Government Committee for Clinical Trials in Andalusia and the Spanish agency for drugs and health products.Trial registration: ClinicalTrials.gov Identifier: NCT01329770 (29 March 2011).

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9. Eskow KG, Chasson GS, Summers JA. {{A Cross-Sectional Cohort Study of a Large, Statewide Medicaid Home and Community-Based Services Autism Waiver Program}}. {J Autism Dev Disord}. 2014 Sep 3.

State-specific 1915(c) Medicaid Home and Community-Based Services waiver programs have become central in the provision of services specifically tailored to children with autism spectrum disorders (ASD). Using propensity score matching, 130 families receiving waiver services for a child with ASD were matched with and compared to 130 families waiting on the registry (i.e., control group). Results indicate that participants in the waiver group reported more improvement in independent living skills and family quality of life over the last year compared to those on the registry. More frequent intensive individual support services and therapeutic integration were statistically predictive of improvement in a variety of domains. The results suggest that the waiver program may be promising for improving child and family functioning.

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10. Gerhardt J, Zaninovic N, Zhan Q, Madireddy A, Nolin SL, Ersalesi N, Yan Z, Rosenwaks Z, Schildkraut CL. {{Cis-acting DNA sequence at a replication origin promotes repeat expansion to fragile X full mutation}}. {The Journal of cell biology}. 2014 Sep 1;206(5):599-607.

Fragile X syndrome (FXS) is caused by CGG repeat expansion that leads to FMR1 silencing. Women with a premutation allele are at risk of having a full mutation child with FXS. To investigate the mechanism of repeat expansion, we examined the relationship between a single-nucleotide polymorphism (SNP) variant that is linked to repeat expansion in haplogroup D and a replication origin located approximately 53 kb upstream of the repeats. This origin is absent in FXS human embryonic stem cells (hESCs), which have the SNP variant C, but present in the nonaffected hESCs, which have a T variant. The SNP maps directly within the replication origin. Interestingly, premutation hESCs have a replication origin and the T variant similar to nonaffected hESCs. These results suggest that a T/C SNP located at a replication origin could contribute to the inactivation of this replication origin in FXS hESCs, leading to altered replication fork progression through the repeats, which could result in repeat expansion to the FXS full mutation.

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11. Grein KA, Glidden LM. {{Predicting well-being longitudinally for mothers rearing offspring with intellectual and developmental disabilities}}. {Journal of intellectual disability research : JIDR}. 2014 Sep 3.

BACKGROUND: Well-being outcomes for parents of children with intellectual and developmental disabilities (IDD) may vary from positive to negative at different times and for different measures of well-being. Predicting and explaining this variability has been a major focus of family research for reasons that have both theoretical and applied implications. METHODS: The current study used data from a 23-year longitudinal investigation of adoptive and birth parents of children with IDD to determine which early child, mother and family characteristics would predict the variance in maternal outcomes 20 years after their original measurement. Using hierarchical regression analyses, we tested the predictive power of variables measured when children were 7 years old on outcomes of maternal well-being when children were 26 years old. Outcome variables included maternal self-report measures of depression and well-being. RESULTS: Final models of well-being accounted for 20% to 34% of variance. For most outcomes, Family Accord and/or the personality variable of Neuroticism (emotional stability/instability) were significant predictors, but some variables demonstrated a different pattern. CONCLUSIONS: These findings confirm that (1) characteristics of the child, mother and family during childhood can predict outcomes of maternal well-being 20 years later; and (2) different predictor-outcome relationships can vary substantially, highlighting the importance of using multiple measures to gain a more comprehensive understanding of maternal well-being. These results have implications for refining prognoses for parents and for tailoring service delivery to individual child, parent and family characteristics.

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12. Harrop C. {{Evidence-based, parent-mediated interventions for young children with autism spectrum disorder: The case of restricted and repetitive behaviors}}. {Autism}. 2014 Sep 3.

Restricted and repetitive behaviors represent a core symptom of autism spectrum disorders. While there has been an increase in research into this domain in recent years, compared to social-communication impairments experienced by children with autism spectrum disorders, much less is known about their development, etiology, and management. Parent-mediated interventions have become increasingly popular in the field, with a surge of studies reporting significant findings in social communication and cognitive development in early childhood. Restricted and repetitive behaviors are often not specifically targeted or measured as an outcome within these interventions. This article reviews how 29 parent-mediated interventions approached the management, treatment, and measurement of restricted and repetitive behaviors. Recommendations for research and practice are presented.

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13. Kargas N, Lopez B, Reddy V, Morris P. {{The Relationship Between Auditory Processing and Restricted, Repetitive Behaviors in Adults with Autism Spectrum Disorders}}. {J Autism Dev Disord}. 2014 Sep 2.

Current views suggest that autism spectrum disorders (ASDs) are characterised by enhanced low-level auditory discrimination abilities. Little is known, however, about whether enhanced abilities are universal in ASD and how they relate to symptomatology. We tested auditory discrimination for intensity, frequency and duration in 21 adults with ASD and 21 IQ and age-matched controls. Contrary to predictions, there were significant deficits in ASD on all acoustic parameters. The findings suggest that low-level auditory discrimination ability varies widely within ASD and this variability relates to IQ level, and influences the severity of restricted and repetitive behaviours (RRBs). We suggest that it is essential to further our understanding of the potential contributing role of sensory perception ability on the emergence of RRBs.

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14. Koh JY, Lim J, Byun HR, Yoo MH. {{Abnormalities in the zinc-metalloprotease-BDNF axis may contribute to megalencephaly and cortical hyperconnectivity in young autism spectrum disorder patients}}. {Molecular brain}. 2014 Sep 3;7(1):64.

Whereas aberrant brain connectivity is likely the core pathology of autism-spectrum disorder (ASD), studies do not agree as to whether hypo- or hyper-connectivity is the main underlying problem. Recent functional imaging studies have shown that, in most young ASD patients, cerebral cortical regions appear hyperconnected, and cortical thickness/brain size is increased. Collectively, these findings indicate that developing ASD brains may exist in an altered neurotrophic milieu. Consistently, some ASD patients, as well as some animal models of ASD, show increased levels of brain-derived neurotrophic factor (BDNF). However, how BDNF is upregulated in ASD is unknown. To address this question, we propose the novel hypothesis that a putative zinc-metalloprotease-BDNF (ZMB) axis in the forebrain plays a pivotal role in the development of hyperconnectivity and megalencephaly in ASD.We have previously demonstrated that extracellular zinc at micromolar concentrations can rapidly increase BDNF levels and phosphorylate the receptor tyrosine kinase TrkB via the activation of metalloproteases. The role of metalloproteases in ASD is still uncertain, but in fragile X syndrome, a monogenic disease with an autistic phenotype, the levels of MMP are increased. Early exposure to lipopolysaccharides (LPS) and other MMP activators such as organic mercurials also have been implicated in ASD pathogenesis. The resultant increases in BDNF levels at synapses, especially those involved in the zinc-containing, associative glutamatergic system may produce abnormal brain circuit development. Various genetic mutations that lead to ASD are also known to affect BDNF signaling: some down-regulate, and others up-regulate it. We hypothesize that, although both up- and down-regulation of BDNF may induce autism symptoms, only BDNF up-regulation is associated with the hyperconnectivity and large brain size observed in most young idiopathic ASD patients.To test this hypothesis, we propose to examine the ZMB axis in animal models of ASD. Synaptic zinc can be examined by fluorescence zinc staining. MMP activation can be measured by in situ zymography and Western blot analysis. Finally, regional levels of BDNF can be measured. Validating this hypothesis may shed light on the central pathogenic mechanism of ASD and aid in the identification of useful biomarkers and the development of preventive/therapeutic strategies.

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15. Matson JL, Cervantes PE. {{Assessing aggression in persons with autism spectrum disorders: An overview}}. {Research in developmental disabilities}. 2014 Aug 29;35(12):3269-75.

Aggression is a commonly co-occurring problem with autism spectrum disorders (ASD). Comorbid aggression can be every bit as debilitating as core symptoms of ASD itself. As a result, careful identification of aggression, the context in which it occurs, and factors that maintain the behavior all have important implications for treatment. As a result, researchers have begun to develop methods and measures to assess aggression among persons with ASD. The purpose of this paper was to review measures that have been used to assess aggression among persons with ASD. We located 25 different assessment methods for both children and adults. The current status and future directions of this area of research are discussed.

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16. Nardone S, Sharan Sams D, Reuveni E, Getselter D, Oron O, Karpuj M, Elliott E. {{DNA methylation analysis of the autistic brain reveals multiple dysregulated biological pathways}}. {Translational psychiatry}. 2014;4:e433.

Autism spectrum disorders (ASD) are a group of neurodevelopmental conditions characterized by dysfunction in social interaction, communication and stereotypic behavior. Genetic and environmental factors have been implicated in the development of ASD, but the molecular mechanisms underlying their interaction are not clear. Epigenetic modifications have been suggested as molecular mechanism that can mediate the interaction between the environment and the genome to produce adaptive or maladaptive behaviors. Here, using the Illumina 450 K methylation array we have determined the existence of many dysregulated CpGs in two cortical regions, Brodmann area 10 (BA10) and Brodmann area 24 (BA24), of individuals who had ASD. In BA10 we found a very significant enrichment for genomic areas responsible for immune functions among the hypomethylated CpGs, whereas genes related to synaptic membrane were enriched among hypermethylated CpGs. By comparing our methylome data with previously published transcriptome data, and by performing real-time PCR on selected genes that were dysregulated in our study, we show that hypomethylated genes are often overexpressed, and that there is an inverse correlation between gene expression and DNA methylation within the individuals. Among these genes there were C1Q, C3, ITGB2 (C3R), TNF-alpha, IRF8 and SPI1, which have recently been implicated in synaptic pruning and microglial cell specification. Finally, we determined the epigenetic dysregulation of the gene HDAC4, and we confirm that the locus encompassing C11orf21/TSPAN32 has multiple hypomethylated CpGs in the autistic brain, as previously demonstrated. Our data suggest a possible role for epigenetic processes in the etiology of ASD.

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17. Polderman TJ, Hoekstra RA, Posthuma D, Larsson H. {{The co-occurrence of autistic and ADHD dimensions in adults: an etiological study in 17 770 twins}}. {Translational psychiatry}. 2014;4:e435.

Autism spectrum disorder (ASD) and attention deficit/hyperactivity disorder (ADHD) often occur together. To obtain more insight in potential causes for the co-occurrence, this study examined the genetic and environmental etiology of the association between specific ASD and ADHD disorder dimensions. Self-reported data on ASD dimensions social and communication difficulties (ASDsc), and repetitive and restricted behavior and interests (ASDr), and ADHD dimensions inattention (IA), and hyperactivity/impulsivity (HI) were assessed in a community sample of 17 770 adult Swedish twins. Phenotypic, genetic and environmental associations between disorder dimensions were examined in a multivariate model, accounting for sex differences. ASDr showed the strongest associations with IA and HI in both sexes (rp 0.33 to 0.40). ASDsc also correlated moderately with IA (females rp 0.29 and males rp 0.35) but only modestly with HI (females rp 0.17 and males rp 0.20). Genetic correlations ranged from 0.22 to 0.64 and were strongest between ASDr and IA and HI. Sex differences were virtually absent. The ASDr dimension (reflecting restricted, repetitive and stereotyped patterns of behavior, interests and activities) showed the strongest association with dimensions of ADHD, on a phenotypic, genetic and environmental level. This study opens new avenues for molecular genetic research. As our findings demonstrated that genetic overlap between disorders is dimension-specific, future gene-finding studies on psychiatric comorbidity should focus on carefully selected genetically related dimensions of disorders.

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18. Potera C. {{Echoes of autism? Inhaled ultrafine particles and brain changes in mice}}. {Environmental health perspectives}. 2014 Sep 1;122(9):A250.

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19. Shivers CM, Plavnick JB. {{Sibling Involvement in Interventions for Individuals with Autism Spectrum Disorders: A Systematic Review}}. {J Autism Dev Disord}. 2014 Sep 2.

Many researchers have studied various interventions for individuals with autism spectrum disorder (ASD). Occasionally, siblings will be included in intervention studies, participating in programs designed to address a number of challenges faced by individuals with ASD. Although sibling involvement in such interventions is not a new phenomenon, there is no consistent method for including siblings in treatment for individuals with ASD. The purpose of this article is to review the existing literature describing sibling involvement in interventions among families of children with ASD, describing patterns of research and targeted outcomes. The authors also identify gaps and areas for future consideration from researchers, clinicians, and families.

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20. Stavropoulos KK, Carver LJ. {{Effect of Familiarity on Reward Anticipation in Children with and without Autism Spectrum Disorders}}. {PloS one}. 2014;9(9):e106667.

BACKGROUND: Previous research on the reward system in autism spectrum disorders (ASD) suggests that children with ASD anticipate and process social rewards differently than typically developing (TD) children-but has focused on the reward value of unfamiliar face stimuli. Children with ASD process faces differently than their TD peers. Previous research has focused on face processing of unfamiliar faces, but less is known about how children with ASD process familiar faces. The current study investigated how children with ASD anticipate rewards accompanied by familiar versus unfamiliar faces. METHODS: The stimulus preceding negativity (SPN) of the event-related potential (ERP) was utilized to measure reward anticipation. Participants were 6- to 10-year-olds with (N = 14) and without (N = 14) ASD. Children were presented with rewards accompanied by incidental face or non-face stimuli that were either familiar (caregivers) or unfamiliar. All non-face stimuli were composed of scrambled face elements in the shape of arrows, controlling for visual properties. RESULTS: No significant differences between familiar versus unfamiliar faces were found for either group. When collapsing across familiarity, TD children showed larger reward anticipation to face versus non-face stimuli, whereas children with ASD did not show differential responses to these stimulus types. Magnitude of reward anticipation to faces was significantly correlated with behavioral measures of social impairment in the ASD group. CONCLUSIONS: The findings do not provide evidence for differential reward anticipation for familiar versus unfamiliar face stimuli in children with or without ASD. These findings replicate previous work suggesting that TD children anticipate rewards accompanied by social stimuli more than rewards accompanied by non-social stimuli. The results do not support the idea that familiarity normalizes reward anticipation in children with ASD. Our findings also suggest that magnitude of reward anticipation to faces is correlated with levels of social impairment for children with ASD.

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21. Summers SM, Cogswell J, Goodrich JE, Mu Y, Nguyen DV, Brass SD, Hagerman RJ. {{Prevalence of restless legs syndrome and sleep quality in carriers of the fragile X premutation}}. {Clinical genetics}. 2014 Aug;86(2):181-4.

This study examined the relationship between the fragile X premutation and restless legs syndrome (RLS). Demographic, medical history and survey responses related to sleep were collected from 213 participants (127 carriers and 86 age matched controls). Subjects were asked about the presence of the four formal diagnostic criteria for RLS. Individuals with the premutation were 1.9 times as likely to meet criteria for RLS (95% CI 1.1-3.2, p=0.025) as controls. Premutation carriers with RLS also experienced significantly worse symptoms than matched controls with adjusted mean scores of 15.1+/-8.8 vs 7.9+/-4.4, respectively on the International Restless Legs Scale (IRLS). As markers for domains of sleep disturbance, all subjects completed the Epworth Sleepiness Scale (ESS), the Insomnia Severity Index (ISA) and the Pittsburgh Sleep Quality Index (PSQI). Premutation carriers demonstrated significantly more pathology on these tests except for the ESS where there was a trend towards increased daytime sleepiness in carriers. RLS joins a host of other conditions that should be carefully screened for in those carrying the fragile X premutation and sleep should be a focus for clinicians providing care to them.

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22. Tang G, Gudsnuk K, Kuo SH, Cotrina ML, Rosoklija G, Sosunov A, Sonders MS, Kanter E, Castagna C, Yamamoto A, Yue Z, Arancio O, Peterson BS, Champagne F, Dwork AJ, Goldman J, Sulzer D. {{Loss of mTOR-Dependent Macroautophagy Causes Autistic-like Synaptic Pruning Deficits}}. {Neuron}. 2014 Sep 3;83(5):1131-43.

Developmental alterations of excitatory synapses are implicated in autism spectrum disorders (ASDs). Here, we report increased dendritic spine density with reduced developmental spine pruning in layer V pyramidal neurons in postmortem ASD temporal lobe. These spine deficits correlate with hyperactivated mTOR and impaired autophagy. In Tsc2+/- ASD mice where mTOR is constitutively overactive, we observed postnatal spine pruning defects, blockade of autophagy, and ASD-like social behaviors. The mTOR inhibitor rapamycin corrected ASD-like behaviors and spine pruning defects in Tsc2+/ mice, but not in Atg7(CKO) neuronal autophagy-deficient mice or Tsc2+/-:Atg7(CKO) double mutants. Neuronal autophagy furthermore enabled spine elimination with no effects on spine formation. Our findings suggest that mTOR-regulated autophagy is required for developmental spine pruning, and activation of neuronal autophagy corrects synaptic pathology and social behavior deficits in ASD models with hyperactivated mTOR.

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23. Tye C, Battaglia M, Bertoletti E, Ashwood KL, Azadi B, Asherson P, Bolton P, McLoughlin G. {{Altered neurophysiological responses to emotional faces discriminate children with ASD, ADHD and ASD+ADHD}}. {Biological psychology}. 2014 Aug 29.

There are high rates of overlap between autism spectrum disorder (ASD) and attention deficit hyperactivity disorder (ADHD). Emotional impairment in the two disorders, however, has not been directly compared using event-related potentials (ERPs) that are able to measure distinct temporal stages in emotional processing. The N170 and N400 ERP components were measured during presentation of emotional face stimuli to boys with ASD (n=19), ADHD (n=18), comorbid ASD+ADHD (n=29) and typically developing controls (n=26). Subjects with ASD (ASD/ASD+ADHD) displayed reduced N170 amplitude across all stimuli, particularly for fearful versus neutral facial expressions. Conversely, subjects with ADHD (ADHD/ASD+ADHD) demonstrated reduced modulation of N400 amplitude by fearful expressions in parietal scalp regions and happy facial expressions in central scalp regions. These findings indicate a dissociation between disorders on the basis of distinct stages of emotion processing; while children with ASD show alterations at the structural encoding stage, children with ADHD display abnormality at the contextual processing stage. The comorbid ASD+ADHD group presents as an additive condition with the unique deficits of both disorders. This supports the use of objective neural measurement of emotional processing to delineate pathophysiological mechanisms in complex overlapping disorders.

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24. van Diessen E, Senders J, Jansen FE, Boersma M, Bruining H. {{Increased power of resting-state gamma oscillations in autism spectrum disorder detected by routine electroencephalography}}. {European archives of psychiatry and clinical neuroscience}. 2014 Sep 3.

Experimental studies suggest that increased resting-state power of gamma oscillations is associated with autism spectrum disorder (ASD). To extend the clinical applicability of this finding, we retrospectively investigated routine electroencephalography (EEG) recordings of 19 patients with ASD and 19 age- and gender-matched controls. Relative resting-state condition gamma spectral power was variable, but on average significantly increased in children with ASD. This effect remained when excluding electrodes associated with myogenic gamma activity. These findings further indicate that increased resting-state gamma activity characterizes a subset of ASD and may also be detected by routine EEG as a clinically accessible and well-tolerated investigation.

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25. Yau VM, Lutsky M, Yoshida CK, Lasley B, Kharrazi M, Windham G, Gee N, Croen LA. {{Prenatal and Neonatal Thyroid Stimulating Hormone Levels and Autism Spectrum Disorders}}. {J Autism Dev Disord}. 2014 Sep 2.

Thyroid hormones are critical for normal brain development. This study examined autism spectrum disorders (ASD) and thyroid stimulating hormone (TSH) levels measured in mid-pregnancy maternal serum and infant blood after birth. Three groups of children born in Orange County, CA in 2000-2001were identified: ASD (n = 78), developmental delay (n = 45), and general population controls (GP) (n = 149). Samples were retrieved from prenatal and newborn screening specimen archives. Adjusted logistic regression models showed inverse associations between ASD and log transformed TSH levels in maternal serum samples (ASD vs. GP: OR [95 % CI] 0.33 [0.12-0.91], Early Onset ASD vs. GP: 0.31 [0.10-0.98]). Results for thyroid levels in newborn blood samples were similar though not significant (ASD vs. GP: 0.61 [0.18-2.04]).

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